Core support is requested for collection and analysis of blood (serum and lymphocytes) and tumor tissues for each project under the overall program. Procedures will include the following. 1. Centralized collection of blood for serum and lymphocytes, and tumor tissues from JWCI and outside patients. Samples will be processed in a uniform manner which will improve the consistency of lab results. Systems will be established to promote efficient use of materials and to reduce the frequency of venipuncture. (Projects I, II and III). 2. Target antigens will be purified from spent serum-free culture medium, tumor cell extracts and urine of melanoma patients. These procedures are well established and material is required for Projects I and III. 3. Analysis of a large number of serum samples for antibody levels to multiple tumor antigens will be required for each project and will be more efficiently undertaken in a core assay (ELISA and RI) service. Additionally, T-cell responses monitored by cytokine release (ELISA) will be determined. (Projects I, II, III). 4. Examination of lymphocyte subsets, antigen expression by melanoma cells and antibody binding to tumor cells will be determined by flow cytometry. (projects I, II and III). 5. Elucidation of specific tumor antigen expression and surface phenotype of infiltrating lymphoid cells in tumor biopsy specimens will be examined by immunohistochemical and histological techniques. (Projects I, II and III).